Bolt-anchor.



T. P. KELLER.

BOLT ANCHOR.

AJPPLIUATION FI ED 13 30.30, 1909.

966,024. Patented Aug. 2, 1910.

INVENTOR- WITNESSES:

U W 1 i I all whom it may concern: I

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PATEN um: lea.

TRAUGOTT F. KELLER, OF BROOKEYN, NEW YORK.

eeaoea.

Be it known that LTBAUGOTT F. KELLER,

a citizen of the United States of America,

. hole and theboltsecured to the anchor.

The particular class of bolt anchor 'to which my invention relates isthat in which a soft metal segmental shell is employed into which theboltis forced; whereby threads are formed by the bolt upon the interiorof the shell and the exterior of the shell is caused to'conformsubstantially to the contour of the hole. I

' My invention consists essentially in a segmental shell of thischaracter, preferably substantially cylindrical upon its exterior andhaving a longitudinal bore theret-hrough which is substantially rectanlar in cross section throughout, two opposite sides of the bore beingparallel andthe other two sides being longitudinally convergent, theline of division between the segments being in a plane substantially atright angles to the In this form of anchor the interior bore issubstantially wedge-shaped in one direction so that the bolt in enteringit would tend to force the segments apart with a wedge-like action,while in the other direction, 71. 6., the direction in which the anchoris not divided into segments and hence in which any wedge-like actionwould be undesirable,-the walls substantially conform to the bolt. Theresult of the foregoing is a tendency to reduce the mutilation of theanchor as the bolt is being forcedin:

'W9.Id, a tendency to increase the size and strength of the threadsformed by the screw, and a general increase of the efliclencyof theanchor both in its grip upon'the walls of the hole in which it ISemployed, and its gri upon the bolt engaging it Iii order that myinvention may be thoroughly understood, I will now proceed pecificationof Letters Patent.

I Application filed December 30, 1909. Serial No. 535,698.

. BOLT-ANCHOR.

Patented Aug. 2, 1910.

ings illustrating the same, and will then point out the novel featuresin claims.

In the drawings: Figure l is a view in" central longitudinal sectionthrough a bolt anchor constructedin accordance with my invention. Fig. 2is a view in central vertical longitudinal section therethrough, at

right angles to the plane of section 'of Fig. 1.

Fig. 3 is an end view of the anchor looking in the direction of thearrow of Fig. 1. Fig. 4 is an end view of the same lookingin thedirection of the arrow of Fig. 2. Fig. 5 is a view in centrallongitudinal sectionthrough a form of bolt anchor in which the the planeof the line 66 of Fig.

.70 segments are entirely separated. Fig. 6 is a transverse sectionalview of the same upon 'Referring first to the construction shown inFigs. 1 to 5%,the bolt anchor comprises a substantially cylindricalshell composed of two segments 10-11 divided longitudinally by slots 12.The slots 12 terminate near the outer end of the bolt anchor insubstantially heart-shaped recesses 13, as shown. The segas in theexample of my invention shown in Figs. Sand 6. The shell is providedwith a longitudinal bore 14 which is substantially rectangular at anypoint in. transverse sec tion throughout the device. Two of the o positesides 15 of this bore are substantial y parallel with each other andwith the axis of the bore, while theother two sides16 are inwardlyconver ent front the outer to the inner end, 2 0., rom the end shown inFig. 3 to the end shown in Fig. 4. The parallel sides 15 are those sideswhich are at right anglesto the lineof division between the segments,2'. 6., the slots 12 in the first four 'fig'fi'fesu In Figs. 5 and 6 Ihave shown another 8O ments in these figures are shown as united videdas in any event the forward end of the anchor is not expanded and theflexibility to dqscribe certain embodiments thereof,

permitfthe inner'ends of the segments to exor malleability of the metal'will readily I pand even though the outer ends be actually united as inthe example shown in the first four figures. It will be also understoodthat it is not essential to terminate the slots 12 in the heart-shapedrecesses 13, but that the same is possible and advantageous under somecircumstances in that it tends to prevent fracture of the segmentsbeyond such points.

What I claim is:

l. A bolt anchor having a longitudinal bore therethrough which issubstantially rectangular in cross section at any point, two oppositesides of the said bore being approximately parallel with respect to eachother, and the other two sides being longitudinally convergent towardthe inner end of the anchor, the said anchor being formed in twosegments divided longitudinally in a plane substantially at right anglesto the parallel sides of the said bore.

2. A bolt anchor comprising a substantially cylindrical shell composedof two segments having a longitudinal bore therethrough which issubstantially rectangular in cross section at any point, two oppositesides of the said bore being approximately parallel with respect to eachother, and the other two sides being longitudinally con vergent towardthe inner end of the anchor, the plane of segmental division beingsubstantially at right angles to the parallel sides of the said bore.

3. A bolt anchor comprising a substantially cylindrical shell having alongitudinal bore therethrough which is substantially rectangular incross section at any point, two opposite sides of the said bore beingapproximately parallel with respect to each other, and the other twosides being longitudinally convergent toward the inner end of theanchor, the said shell being provided with slots extending from theinner end part of the distance to the outer end of the shell, the saidslots dividing the shell into two segments substantially upon a plane atright angles to the parallel sides of thebore.

4. The combination with a bolt anchor having a longitudinal boretherethrough 'which is substantially rectangular in cross said bore.

In witness whereof, I have hereunto set my hand this 27th day ofDecember, 1909. TRAUGOTT F. KELLER. Witnesses t l ln'Nnr EURING, John G.GLYNN.

